The mountains of Pluto are snowcapped, but not for the same reasons as on Earth:
In 2015, the New Horizons space probe discovered spectacular snowcapped mountains on Pluto, which are strikingly similar to mountains on Earth.
[...] An international team led by CNRS scientists1 conducted this exploration. They first determined that the "snow" on Pluto's mountains actually consists of frozen methane, with traces of this gas being present in Pluto's atmosphere, just like water vapor on Earth. To understand how the same landscape could be produced in such different conditions, they used a climate model for the dwarf planet, which revealed that due to its particular dynamics, Pluto's atmosphere is rich in gaseous methane at altitudes.
[...] it is only at the peaks of mountains [...] that the air contains enough methane for it to condense.
The homologous structures are striking.
Journal Reference:
Tanguy Bertrand, François Forget, Bernard Schmitt, et al. Equatorial mountains on Pluto are covered by methane frosts resulting from a unique atmospheric process [open], Nature Communications (DOI: 10.1038/s41467-020-18845-3)
(Score: 4, Funny) by looorg on Wednesday October 14 2020, @11:28AM
So there are not snow on the mountains tops of Pluto cause it's bloody cold out there? Like there tends to be on earth. Where are the sandy beaches of Pluto?
(Score: 0) by Anonymous Coward on Wednesday October 14 2020, @03:43PM
You would notice the snow is slightly yellow-tinged.
Now you know why they named the planet* "pluto."
* Once a planet, always a planet.
(Score: 1) by oumuamua on Wednesday October 14 2020, @11:35PM
Can you ski on them????
(Score: 0) by Anonymous Coward on Thursday October 15 2020, @06:26AM
Pluto has an unusual atmospheric structure. There's a very thin planetary boundary layer on Pluto, which might quality as a very thin troposphere. Aside from that thin boundary layer, Pluto really doesn't have a troposphere, but instead the stratosphere essentially begins at the surface. Basically, the atmosphere warms with height instead of cooling with height in the lowest layer of Earth's atmosphere. The closest situation like that on Earth is probably Antarctica, where there is a very strong temperature inversion. I don't know that much about Pluto's climate but, if I had to guess, the vertical structure probably arises from katabatic winds, where cold air flows down sloping terrain. There are very similar katabatic winds in Antarctica. In Pluto's case, the sunlight is so dim that it probably doesn't heat the surface much, so there's probably not much in the way of convection to overturn the inversion.
We get snow capped mountains on Earth for two basic reasons. When winds come into contact with mountains, air has to ascend up and over the mountains. The rising air cools adiabatically, eventually producing clouds and precipitation if there's enough moisture and if the air cools enough. We typically use terms like upslope flow and orographic lift to describe this process. On Earth, temperatures cool with height over a deep enough layer that even the summit of Mount Everest is still usually below the tropopause. Because temperatures are cooler at higher altitudes, it's more likely to be colder at the summit of mountains instead of at lower altitudes. That's simply not the case on Pluto, where it's warmer at higher altitudes.
Simulating Pluto's atmosphere really isn't that different from our climate models of Earth. Here's a paper that describes the global climate model to simulate Pluto's climate: https://www.boulder.swri.edu/~layoung/eprint/Forget+2017_Icarus_287_54.pdf [swri.edu]. It really isn't very different from models we use for simulating Earth's climate. The relevant part of the paper to this story is section 2.8.